Hi Eunice,
If you are unable to come on Friday, then consider coming on Sunday around 11am. There will be many people there. If you tell anyone that you are tying to learn more about Islam, I am sure they will be happy to assist. Other than that the mosque is open from morning prayers (6:00am) till night prayers (9:00pm). During this time people come to the mosque to make salat (prayers) and leave. As for the proper dress for a woman while in the mosque, you are correct and there are many sisters who would be more than happy to assist you with that. There small is a community member store on mosque premises that sells the cloth for head and its called Hijab.
I am not a mosque leader. I am a man and a community member just like any other person in the community. There are many sisters at the mosque who can assist you in any way you like. I am very happy that you have chosen to learn more about Islam. There classes at the mosque for children as well as adults. Also none of your questions are offending, so please don't hisitate to ask more questions.
Thanks